Relate the 'very odd' incident that Enfield tells Utterson.

Enfield relates the incident in which he saw a disfigured man roaming the streets in the wee hours of he morning. The man in question was responsible for running down an eight year old girl. Rather than call the police, the witnesses blackmail the man, something he agrees to and returns with a check signed by Enfield's personal friend, Dr. Jekyll. When Enfield went to cash the check, he was shocked to find that it was valid and surmised the man was blackmailing Jekyll.